Lap Times
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Free Online Stopwatch with Full Lap Timing
Need a precise stopwatch that does more than just count? This tool gives you millisecond-accurate timing with professional lap/split tracking, automatic best/worst/average statistics, CSV export for data analysis, and a fullscreen chronograph mode. No app install, no signup, no ads.
Why AI Cannot Replace This Tool
AI chatbots can describe how a stopwatch works or suggest timing intervals, but they cannot run a real-time timer. Real-time millisecond precision timing requires continuous browser execution that AI models cannot provide. This is a pure problem-solver for situations requiring actual timing, not just information about timing.
How to Use
- Start / Stop — Press Start (or Space) to begin timing. Press again to pause. The display shows elapsed time with 10ms precision.
- Lap Recording — While running, press Lap (or L) to record a split. The lap table shows lap number, split time, lap time, and the difference from the previous lap.
- Statistics — After recording laps, the stats panel automatically shows total laps, best lap (green), worst lap (red), and average lap time.
- Export & Copy — Export all lap data as CSV for spreadsheet analysis, or copy to clipboard as formatted text.
- Fullscreen — Press F to enter fullscreen mode for a clean, distraction-free chronograph view. Esc to exit.
Use Cases
| Scenario | How Stopwatch Helps |
|---|---|
| Running / Athletics | Track split times per lap, analyze best/worst, export for training log |
| Swimming | Record lap times with millisecond precision, compare interval consistency |
| Manufacturing QA | Measure cycle times, identify slowest operations, export for analysis |
| Speedrunning | Precise millisecond timing with split recording for routing analysis |
| Cooking | Track multiple step timings, see which steps take longest |
| Time Studies | Record task durations, calculate averages, export to CSV for reporting |
Keyboard Shortcuts
| Key | Action |
|---|---|
| Space | Start / Stop the stopwatch |
| L | Record a lap / split |
| R | Reset everything |
| F | Toggle fullscreen mode |
| Esc | Exit fullscreen |
Why This Stopwatch Is Different
- Real precision — Uses
performance.now()for sub-millisecond accuracy, not imprecisesetIntervalaccumulation - Lap insights — Automatically calculates best, worst, and average lap times — physical stopwatches can't do this
- Data export — CSV export and clipboard copy let you move data to spreadsheets for analysis
- Fullscreen chronograph — Minimal, focused display for race timing
- Keyboard-driven — All functions accessible without mouse for fast operation
- 100% offline — Once loaded, works without internet. No tracking, no data sent anywhere
Frequently Asked Questions
How accurate is this stopwatch?
It uses performance.now() with microsecond-resolution timestamps. Display updates every 10ms (centiseconds). Practically as accurate as any hardware stopwatch.
Can I export my lap data?
Yes. Click "Export CSV" to download a CSV file with all lap data. Click "Copy" to copy formatted text to your clipboard.
Does the stopwatch keep running if I switch tabs?
Yes. The timer continues via performance.now()-based tracking. Display updates via requestAnimationFrame when the tab is visible.
Is this free? Are there ads?
100% free. No ads, no signup, no tracking. All timing happens in your browser. Your data never leaves your device.